FES8FTHE3/45 Equivalent & Substitute Parts

Part Overview

The FES8FTHE3/45 is a general-purpose rectifier diode manufactured by Vishay General Semiconductor - Diodes Division, rated for 300 V DC reverse voltage and 8 A average rectified current in a TO-220AC through-hole package. This part is classified as obsolete, making equivalent and substitute parts necessary for ongoing design support and procurement continuity. The diode features fast recovery characteristics with a 50 ns reverse recovery time and is qualified to AEC-Q101 automotive standards. Identification of compatible alternatives ensures design flexibility and supply chain resilience.

Key Parameters

Parameter	Value	Unit
Voltage - DC Reverse (Vr) (Max)	300	V
Current - Average Rectified (Io)	8	A
Voltage - Forward (Vf) (Max) @ If	1.3 @ 8 A	V
Reverse Recovery Time (trr)	50	ns
Current - Reverse Leakage @ Vr	10 @ 300 V	µA
Speed Classification	Fast Recovery ≤ 500ns, > 200mA (Io)	—
Mounting Type	Through Hole	—
Package / Case	TO-220-2	—
Operating Temperature - Junction	-55 to 150	°C
RoHS Status	ROHS3 Compliant	—
AEC-Q101 Qualification	Yes	—

Substitute Part Grouping Explanation

Substitute parts for the FES8FTHE3/45 are classified based on electrical parameter equivalence and mechanical compatibility. The primary substitution criteria are:

Critical Parameters for Substitution:

Voltage - DC Reverse (Vr) (Max): 300 V minimum
Current - Average Rectified (Io): 8 A minimum
Package / Case: TO-220-2
Mounting Type: Through Hole
Speed Classification: Fast Recovery ≤ 500ns, > 200mA (Io)

Substitution Categories:

Direct Parametric Equivalents (300 V, 8 A): Parts meeting or exceeding all critical electrical parameters with identical voltage and current ratings. These include FES8FT-E3/45, STTH803D, ER803_T0_00001, SDUR830, SFA805GHC0G, SFA805G C0G, and UF803_T0_00001. All maintain TO-220-2 packaging and fast recovery characteristics.

Reduced Current Rating (300 V, 6 A): The LQA06T300 operates at 300 V but with reduced current capacity of 6 A. This part is suitable only for applications where the circuit current requirement does not exceed 6 A.

Elevated Voltage Rating (600 V, 3 A): The LXA03T600 provides higher voltage capability at 600 V but with significantly reduced current capacity of 3 A. This part is suitable only for applications requiring higher voltage blocking capability with lower current demands.

Parameter Comparison

Manufacturer Part Number	Manufacturer	Vr (Max) [V]	Io [A]	Vf (Max) @ If [V]	trr [ns]	Ir @ Vr [µA]	Product Status	Tj (Max) [°C]	RoHS Status
FES8FTHE3/45	Vishay General Semiconductor	300	8	1.3 @ 8 A	50	10 @ 300 V	Obsolete	150	ROHS3 Compliant
FES8FT-E3/45	Vishay General Semiconductor	300	8	1.3 @ 8 A	50	10 @ 300 V	Active	150	ROHS3 Compliant
SFA805GHC0G	Taiwan Semiconductor Corporation	300	8	1.3 @ 8 A	35	10 @ 300 V	Active	150	ROHS3 Compliant
STTH803D	STMicroelectronics	300	8	1.25 @ 8 A	35	20 @ 300 V	Active	175	ROHS3 Compliant
ER803_T0_00001	Panjit International Inc.	300	8	1.3 @ 8 A	35	1 @ 300 V	Active	150	ROHS3 Compliant
SDUR830	SMC Diode Solutions	300	8	1.3 @ 8 A	45	10 @ 300 V	Active	150	ROHS3 Compliant
SFA805G C0G	Taiwan Semiconductor Corporation	300	8	1.3 @ 8 A	35	10 @ 300 V	Active	150	ROHS3 Compliant
UF803_T0_00001	Panjit International Inc.	300	8	1.3 @ 8 A	50	1 @ 300 V	Active	150	ROHS3 Compliant
LQA06T300	Power Integrations	300	6	1.9 @ 6 A	11.5	25 @ 300 V	Active	150	RoHS Compliant
LXA03T600	Power Integrations	600	3	3.1 @ 3 A	20	250 @ 600 V	Active	150	RoHS Compliant

Engineering Selection Recommendations

Primary Substitutes (Full Electrical Equivalence):

The following parts provide complete electrical and mechanical compatibility with the FES8FTHE3/45 and are recommended as direct replacements:

FES8FT-E3/45 (Vishay General Semiconductor): Active product status with identical electrical specifications. Preferred for design continuity within the same manufacturer family.
STTH803D (STMicroelectronics): Active product with improved reverse recovery time (35 ns vs. 50 ns) and extended maximum junction temperature (175°C vs. 150°C). Suitable for applications requiring enhanced thermal performance.
ER803_T0_00001 (Panjit International Inc.): Active product with superior reverse leakage current (1 µA vs. 10 µA), beneficial for low-leakage applications.
UF803_T0_00001 (Panjit International Inc.): Active product with reverse recovery time matching the original specification (50 ns) and low reverse leakage current (1 µA).
SDUR830 (SMC Diode Solutions): Active product with electrical parameters closely matching the original part. Note: REACH Status is Affected.
SFA805GHC0G and SFA805G C0G (Taiwan Semiconductor Corporation): Active products with improved reverse recovery time (35 ns) and specified junction capacitance (60 pF @ 4 V, 1 MHz).

All primary substitutes maintain AEC-Q101 automotive qualification or equivalent compliance, ROHS3 compliance, and TO-220-2 packaging.

Secondary Substitutes (Reduced Current Rating):

LQA06T300 (Power Integrations): Suitable only for applications where circuit current does not exceed 6 A. Offers significantly faster reverse recovery time (11.5 ns) and is part of the Qspeed™ series.

Secondary Substitutes (Elevated Voltage Rating):

LXA03T600 (Power Integrations): Suitable only for applications requiring 600 V blocking capability with maximum current limited to 3 A. Part of the Qspeed™ series with 20 ns reverse recovery time.

Frequently Asked Questions (FAQ)

Q: Can FES8FT-E3/45 be used as a direct replacement for FES8FTHE3/45?

A: Yes. FES8FT-E3/45 is an active product from the same manufacturer with identical electrical specifications: 300 V reverse voltage, 8 A average rectified current, 1.3 V forward voltage at 8 A, and 50 ns reverse recovery time. Both parts use TO-220-2 packaging and meet ROHS3 compliance.

Q: What is the difference between the 8 A and 6 A rated substitutes?

A: The LQA06T300 is rated for 6 A average rectified current compared to 8 A for the FES8FTHE3/45. This part is suitable only for circuits where the maximum current requirement does not exceed 6 A. The 6 A part offers faster reverse recovery (11.5 ns) but higher forward voltage (1.9 V @ 6 A).

Q: Why would I select a 600 V part like LXA03T600 instead of a 300 V part?

A: The LXA03T600 is selected only when the application requires higher voltage blocking capability (600 V) than the original 300 V specification. This part is limited to 3 A current and is not suitable for applications requiring 8 A operation.

Q: Are all substitute parts automotive qualified?

A: The primary substitutes FES8FT-E3/45, SFA805GHC0G, and SFA805G C0G carry AEC-Q101 automotive qualification matching the original part. Other substitutes (ER803_T0_00001, SDUR830, UF803_T0_00001, STTH803D) are active products suitable for general-purpose applications. LQA06T300 and LXA03T600 are not explicitly listed with AEC-Q101 qualification.

Q: What is the significance of reverse recovery time differences?

A: Reverse recovery time (trr) affects switching speed and electromagnetic interference characteristics. The original FES8FTHE3/45 specifies 50 ns. Substitutes with shorter trr values (35 ns for STTH803D, SFA805GHC0G, SFA805G C0G, ER803_T0_00001; 11.5 ns for LQA06T300; 20 ns for LXA03T600) provide faster switching but may require circuit design verification for compatibility.

Q: What does reverse leakage current indicate?

A: Reverse leakage current (Ir) is the small current flowing through the diode when reverse biased. The original part specifies 10 µA @ 300 V. Lower values (1 µA for ER803_T0_00001 and UF803_T0_00001) indicate superior reverse blocking characteristics, beneficial for low-power or precision applications. Higher values (20 µA for STTH803D, 25 µA for LQA06T300, 250 µA for LXA03T600) may impact standby power consumption.

Q: Are there packaging differences between substitutes?

A: All primary substitutes use TO-220-2 through-hole packaging identical to the original FES8FTHE3/45. Packaging variations (Tube vs. unspecified) relate to supply format only and do not affect electrical or mechanical compatibility.

Q: What is the impact of forward voltage differences?

A: Forward voltage (Vf) affects power dissipation and circuit efficiency. The original part specifies 1.3 V @ 8 A. STTH803D offers slightly lower Vf (1.25 V @ 8 A), reducing power loss. LQA06T300 specifies higher Vf (1.9 V @ 6 A) due to its lower current rating. LXA03T600 specifies significantly higher Vf (3.1 V @ 3 A) due to its elevated voltage rating.

Q: Can I use SDUR830 in automotive applications?

A: SDUR830 is an active product with electrical specifications matching the original part. However, its REACH Status is listed as Affected, whereas the original FES8FTHE3/45 is REACH Unaffected. Compliance verification with specific regulatory requirements is necessary before selection for regulated applications.

Q: What is the maximum junction temperature consideration?

A: The original FES8FTHE3/45 specifies -55°C to 150°C operating temperature range. STTH803D extends this to 175°C maximum, providing improved thermal margin. LQA06T300 and LXA03T600 specify 150°C maximum. Selection depends on circuit thermal environment and design margin requirements.

Request Quote (Ships tomorrow)

Part Number

Quantity

Company

Contact Name

E-mail

Message